Bicycle Mechanics - 10 speed 105 compatibility with 12-36 cassette

I have just tried to fit a shadow rear mech with 105 shifters to suit a 12-36 cassette and found they have changed the pull ratio. Is there another 10 speed rear mech I can use?
:notamused:

I don't think you want a 10-spd RD. The 9-spd RD have the correct pull ratio. My wife has 105 on her single with an 11-36 10-spd cassette and a Deore RD

I don't think you want a 10-spd RD. The 9-spd RD have the correct pull ratio. My wife has 105 on her single with an 11-36 10-spd cassette and a Deore RD
This is spoke for truth... The RD should be a 9spd for the 105 shifters.

Yes. 7, 8, and 9 speed MTB rear Shimano derailleurs work with 10 speed road shifters and cassettes. The newer 'Dyna-Sys' rear derauilleurs will not work with road shifters, only with the 'Dyna-Sys' mtb shifters.

An Ultegra 6600 GS (med cage) would work also, I use one on a 10sp with 32t large cog.

You may also want to avoid the Shadow models. My understanding is they may work, but the others work better.

An Ultegra 6600 GS (med cage) would work also, I use one on a 10sp with 32t large cog.

With a 36T cog? Doubt it, I'd just get a MTB RD.

+1 Any non-DynaSys Shimano MTB RD will work, like a 9-speed Deore, LX, XT, XTR, etc.

With a 36T cog? Doubt it, I'd just get a MTB RD.

+1 Any non-DynaSys Shimano MTB RD will work, like a 9-speed Deore, LX, XT, XTR, etc.

I stand corrected.
It does work with a 28 and a 32 though.

I have a 9 speed rear xt with 105 10 speed shifters on my touring bike, works fine.

An Ultegra 6600 GS (med cage) would work also, I use one on a 10sp with 32t large cog.

Are you telling me that your Ultegra 6600 (medium cage) can do a 32t on your bike without issue(s)?

Are you telling me that your Ultegra 6600 (medium cage) can do a 32t on your bike without issue(s)?

It's not uncommon, there's a lot of leeway depending primarily on the derailleur hanger's orientation relative to the rear axle. There's certainly no guarantee it will work, but it might; and there's a possibility it will work, but not well.

One of the most common mistakes on this forum is when folks post definitively about a rear derailleur working with a largest cog that's well beyond the derailleur's stated spec. Folks need to understand that it might work, it might not. Trying it on a particular bike is the only way to know for sure. I've seen bikes with 27t largest cogs equipped with Shimano road derailleurs rated for a 27t largest cog, and the upper derailleur pulley hits the largest cog unacceptably even when the b screw is screwed all the way in. Bottom line: the results will vary from one bike to another.

You may also want to avoid the Shadow models. My understanding is they may work, but the others work better.

You are right, I have just tried a 9sp Shadow and it almost works. I can get it working fairly well but I think once it wears a bit it will be a constant fiddling nightmare to keep it so.

You may also want to avoid the Shadow models. My understanding is they may work, but the others work better.

You are right, I have just tried a 9sp Shadow and it almost works. I can get it working fairly well but I think once it wears a bit it will be a constant fiddling nightmare to keep it so.:twitchy:

Shimano recommends Shadow RD's for 12-36 (HG61):
M772 Deore XT 9
M662 SLX 9
M592 Deore 9
M810 Saint 9